1. Technical Field
This technology pertains generally to digital microscopy, and more particularly to a portable imaging system compatible with the camera of a smart phone or tablet to capture and analyze microscopic images of a sample in an automated manner.
2. Background Discussion
Traditional microscopes are powerful measurement tools that are used in biology to understand fundamental processes and used clinically to determine whether a disease is present in a sample. These devices normally require significant investment to purchase as well as skilled technicians to use them and regular power for operation. While there are mechanical systems that can be attached to microscopes to automatically acquire images thereby reducing the time required of an operator, current implementations add significantly to cost and still require someone with a reasonable amount of skill to use. This has confined microscopes, both manual and automated, to centralized settings where these resources are available. The domains in which microscopes are used, including clinical diagnostics and laboratories in low-resource settings, would benefit from simplified automated instrumentation with a lower required level of operator skill and utilize a convenient interface with the technology, such as that provided by a touch screen. In clinical diagnostic use, for example, making a measurement at the point of care could enable a faster and more actionable diagnosis, while measurements for water quality would benefit from utilizing freshly prepared samples.
One limitation of current portable imaging systems is that a user must collect images one at a time under manual control. Many microscopy applications demonstrate increased sensitivity when scanning a larger area and inspecting more of the sample. Because of this relationship, it will take a significant amount of time from the user to reach a target level of sensitivity and specificity for certain microscopic assay using current systems.
Another limitation of current microscopy systems capable of distributed use is that it can be challenging for someone without significant training to bring the sample into focus before acquisition. Being able to execute this procedure establishes a minimum level of skill to capture usable images from the sample. Even for trained users, focusing on relevant features in each field adds to the time required to capture images.
Finally, current systems are also unable to immediately analyze the sample and provide an assessment of the sample content on the device itself. They traditionally require a trained interpreter to be on-site or require remote transmission for telemedicine. Applications such as counting tuberculosis bacilli using on-board image processing are thus beyond the capabilities of fully integrated, portable solutions.
In conclusion, there is a need for a low cost portable device with hardware and software automation that can achieve automated sample scanning and focused imaging and be used by a minimally trained operator. Such a system would enable decentralized point-of-collection analysis of clinical and research samples for transmission or on-board analysis.